Apple recently announced on its dev center website that anyone submitting a new app must optimize it for iOS 7, beginning February 1.
According to the iPhone maker, “new apps and app updates submitted to the App Store must be built with the latest version of Xcode 5 and must be optimized for iOS 7.”
Apps and new updates must be optimized in order for Apple to accept them and allow them into the App Store.
In our experience, most apps we use have been updated. The only ones that aren’t are apps that have sat untouched by their developers for years already. If anything, seeing which apps are updated now just shows us who cares about their apps and who doesn’t.
It’s a good idea to update those apps. iOS 7 is seeing a high adoption rate.